Water-tube boiler.



M. W. SEWALL & D. S. JAUOBUS.

WATER TUBE BOILER.

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3 SHEETSSHEET l.

WITNESSES WCW A TTORNEYS M. W. SEWALL & D. S. JACOBUS.

WATER TUBE BOILER.

APPLICATION FILED FEB. 11, 1909.

Patented Jan. 31, 1911.

3 SHEETS-SHEET 2.

WITNESSES INVENTORS M. W. SEWALL & D. s. JAOOBUS.

WATER TUBE BOILER.

APPLICATION FILED FEB. 11, 1909.

Patented Jan. 31, 1911.

3 SHEETSSHEET 8.

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4 Wok/VHS Fro IMINOTT W. SEWALL, OF ROSELLE, AND DAVID S. JACOLBUS, OF JERSEY CITY, NEW JERSEY, ASSIGNORS TO THE BAIBCOCK AND WILCOX COMPANY, OF BAYONNE, NEW JERSEY, A CORPORATION OF NEW JERSEY.

VVATER-TUBE BOILER.

Specification of Letters Patent.

Patented Jan. 31, 1911.

Application filed February 11, 1909. Serial No. 477,410.

and DAVID S. JAcoBUs, citizens of the United States, and theformer a resident of Roselle, county of Union, and State of New Jersey, and the latter of Jersey City, county of Endson, in said State, have invented a new and useful Improvement in lVater-Tube Boilers, of which the following is a specification.

A standard form of boiler, inclusive of boiler construction proper e. the bank of water tubes, the headers, the steam and water drum, the mud drum and their connections) and the setting thereof, is, aside from certain details, shown in Letters Patent of the United States No. 318,501, hIa-y 26, 1885, and with a chain grate in No. 443,110, December 23, 1890. In this construction, the setting (inclusive of furnace, battles, and up-take) is so arranged that the gases make three transverse passes in the bank of tubes. The first pass is at the .steam up-take end of the tubes and forms substantially an upward extension of the furnace, the tubes in this first pass constituting a perforated roof of the furnace and the gases rising from the grate surface through said roof either without any halliing whatsoever, as shown in said Patent. No. 318,501, or with-zsuch ballling as is shown in said Patent No. 443,110 or in Patent 546,115) dated September 10, 1895.

In the construction above referred to, under conditions not unusual e1ther with forced draft or induced draft, the flame eX- tends up intoor beyond the first pass and, while with the non-volatile grades of coal said construction can be run above rating without objectionable smoke, nevertheless ithas long been known that with the highly volatile grades of coal said construction was very seriously objectionable on account of smoking and the nuisance incident thereto. A problem, therefore, which the present invention is intended to solve, is to so set said standard form of watertube boiler construction as to enable it to be operated by highly volatile, bituminous coal with high steaming capacity and eificiency, and substantially Without smoke. To this end, we inter-pose between the grate surface and said standard form of boiler construction, such a structure that the gases before coming in contact to a substantial extent with the Water-tubes are carried below said second pass substantially toward the rear of the boiler and thence back to the said first pass before entering upon the course that they have heretofore taken through said bank of tubes. In this manner, we have ascertained by experiment that we can, with highly volatile grades of bituminous coal, hold the fiame substantially back from said first pass and still maintain the accustomed steaming capacity and efficiency of said boiler construction substantially without the smoke nuisance.

In the accompanying drawings, Figure 1 is a sectional elevation of a boiler containing" our invention. Figs. 2 and 3 are sectional elevations of the lower portions of boilers containing two modified forms of our invention. Fig. 4 is a detail section on the line 4:, 4 of Fig. 2. Fig. .5 is a detail section on the line 5, 5 of Fig. 2. Figs. 6 and 7 are modified details.

The bank of tubes 1, the headers 2, 3 (which may be sectional or otherwise) the steam and water-drum 4, the mud drums 17, and their connections, are of the standard water-tube boiler construction above referred to in which said bank of tubes usually contains from nine horizontal rows of tubes, as herein shown, up to fourteen.

A, B and C are the three transverse passes which have proved to impart the conditions forsatisfactory steam producing and efiiciency of said boiler construction, the gases passing first upward through A, then downward through B, then upward through C to the up-take' The grate 5 (which we have shown as a hand stoked grate, but which may be automatically stoked) is located substantially beneath said first pass A, but the gases are compelled before reaching said first pass A to travel through passages backward beneath said pass B and thence forward again beneath said pass B to said pass A. In the drawing we have shown a backward travel equal to nearly the full width of said.

shown in either, Fig. l, 2 or 3, and another battle 8 extending forwardly from the rear wall 9 and approximately parallel with the baflie 6 to the foot of the baflie 10 by which thefirst pass A is separated from the second pass B; These baflies produce the passage Y leading from the grate over the bridgewall 11 to a point underneath the pass B or C and a passage Z leading thence back again to the pass A.

In all of the figures, the battle 8 is shown as extending beneath its supporting lower row of tubes so that it prevents contact between the gases in the passage Z and said lower row of tubes. In all the figures, the gases in the passage Z are also removed from contact with water-tubes below and in all the figures the gases are removed from contact with water-tubes while in the passage Y. This is done in the construction in Fig. 3 by building the baflie 6 as a fire-brick arch without the presence of any water-tubes beneath the passage Z. In the construction of Figs. 1 and 2, it is done by burying the row of water-tubes 12 in the battle 6, as shown in detail in Fig. 4.

It is true that in the construction shown in Fig. 1, the gases are exposed as they pass from the passage Y to the passage Z to the row of water-tubes 12, but this exposure is comparatively so transient as to be substantially negligible and is only utilized as a convenient way of support of the baflie 6. In Fig. 2, in order to obviate this exposure and at the same time retain the-water-tubes 12 for the support of the-battle 6, we have provided at the rear end of the baflie 6 a manifold 13 for the row of tubes 12, as shown in Fig. 5; this manifold to be connected with the water circulation by.,the. pipe 14. We

also provide a'fire-brick protection 15 for the manifold 13, which is supported on the water-tube. 16 connected with the water circulation by the pipes 17 and 18. Although the water-tube 16 is exposed to the gases, it is less likely to burn out than would be the manifold 13. This brick protection 15 to the manifold 18 serves another purpose, 2'. 6.,

it so baflies the flame passing it as to cause its deflection toward the floor and a further mixing of the gas and air is caused and the flame thereby becomes shorter. That is to say, combustion is completedat' a point nearer to the grate (in the course of the gas passage) than it would otherwise be. This has been proven by experiment by using in place of 15 arched brick walls. It is, however, impossible to maintain such walls when high rates of combustion are employed.

As alternative forms for the support of 1 the battle 6 omitting the row of tubes 12, we

may adopt the construction shown in detail in Fig. 6 or 7. In Fig. 6, the extreme end of the battle 6 is supported by the box 13 which should be connected in the water circulation.

In-Fig. 7 the two side by side pipes 13"- concess we provide a cleaning out door 16.

So far as we know, suggestions that have been heretofore made in the water tube boiler art of causing the gases to pursue a circuitous route from the fire toward the back of the boiler and thence forward again to a transverse pass, have proceeded upon the theory of causing the gases duringsucli circuitous passage to generate steam and pursuant to such theory or principle watertubes of the boiler have been arranged'in accordance with the intention that the gases during such circuitous passage should give up their heat to the generation of steam. The theory and principle of our invention is directly the opposite. Our rinciple is not to have the gases give up the1r heat for the purpose of generating steam during their circuitous passage or until they reach the first transverse pass of the standard con struction above referred to. Proceeding according to this principle, we so protect the gases while prolonging their courseto said first transverse pass that the flame from the clear flame as distinguished from a smoky flame and still the temperature of the gases as they enter said first pass is high enough (say, above 1500 to maintain that degree of evaporation and that efliciency which have characterized the operation of the standard boiler-above referred to. v In normal operation the flame should terminate in the passage Z, where in particular the flame should be isolated from water-tubes in order that the flame may terminate under what we may call hot blast flame conditions, such as are secured by composing the walls of said passage Z substantially of fire brick and thus making said passage substantially devoid of water-tubes for the generation of steam interfering substantially with the maintenance of such hot blast tions.

fire on the grate will register higher than when placed in the passage Z, nevertheless the total or available'h'eat in the gases is greater at the point where the flame burns out than it is immediately above the fire on the grate The apparent contradiction of thisfact by the pyrometer is probably due to the efl'ect on it of the radiant heat which is most intense immediately above the fire on the grate.

With'the standard boiler construction in-' elusive of standard setting above referred to Although a pyrometer placed above the of tubes was about 7 or 8 feet. By our present construction, this height is increased very little, say, one foot, more or less.

As shown in the drawings, we provide a chamber Y back of the bridge wall. The

' contraction of the passage Y-from the furnace chamber by a retarding of the flow of gases assists in'maintaining a high temperature above the fuel bed. The chamber Y into which the gases are discharged from contracted passage Y allows an expansion and mixture of the gases .within it previous to the entrance to the passage Z in which combustion is completed. Chamber Y must, with some qualities of coal, be enlarged to a considerable depth to allow for the deposit of slag-forming material which is carried over from the fire. Otherwise, it will very soon become so clogged with slag that the rate of combustion will be seriously curtailed.

' Having thus described our invention, what we claim is 1. In "a water tube boiler, in combination, a bank of inclined water tubes, a plurality of transverse baffles dividing said bank into transverse passes beginning at the steam uptake end, a furnace and a bridge wall therefor, a baffle 6 extending from the front wall above and to a point beyond the bridge wall, and a bafile 8 above the battle 6 and extending from the rear wall to the first transverse battle, said bridge wall and bafiies forming passages extending from the furnace rearward and then forward to the steam uptake end of the boiler.

2. In a water tube boiler, in combination, a bank of inclined water tubes, aplurality of transverse baifies dividing said bank into transverse passes beginning at the steam uptake end, a furnace and a bridge wall there for, a combustion chamber at the rear of the bridge wall, a baffle forming a roof for said furnace extending beyond the bridge wall,

a second baffle extending from the rear wall forwardly to the first transverse pass and protecting the lower row of tubes.

3. In a water tube boiler, in combination, the bank of inclined water tubes, means whereby the same is divided into a plurality of transverse passes beginning at the steam uptake end, a fuel chamber below the first pass, abridge wall at the rear of said fuel chamber, a combustion chamber at the rear of the bridge wall, a battle 6 forming a roof for said fuel chamber extending beyond the bridge wall, a second baffle forming with I said battle 6 a passage communicating with and forming a continuation of said combustion chamber and discharging into the first pass, said combustion chamber and passage being substantially devoid oftubes for generating steam.

.4. In a water tube boiler, in combination, the bank of inclined water tubes, means whereby the same is divided into a lurality of transverse passes beginning at tie steam uptake end, a fuel chamber, a bridge wall at the rear thereof, an enlarged combustion chamber at the rear of the bridge wall, a

baflie'G forming a roof for said fuel chan1- the uptake end of the boiler, said second I baffle forming with the battle 6 a passage communicating with and forming a continuation of said enlarged combustion chamber, said passage and chamber being substantially devoid of tubes for generating steam.

5. In a water tube boiler, in combination, a bank of inclined water tubes, a furnace, a roof extending from the front of the boiler toward the rear thereof and separating the fuel chamber from the lower row of tubes; a longitudinal bafiie extending from the rear towardthe front and inclosing the tubes of the lower row a part of their length, and a plurality of transverse baffies dividing the space above said longitudinal baffle into a plurality of passes, said roof and longitudinal bafl le forming a gas passage substantially devoid of tubes for generating steam and leading to the first pass.

6. In a water-tube boiler, in combination, the bank of inclined water-tubes, means whereby the same is divided into a plurality of transverse passes beginning at the steam up-take end, the grate extending beneath the first pass, the bridge wall, a bathe 8 extending from the first pass under and adjacent to the second pass, a lower battle 6 extending substantially parallel with said tubes beneath said first and second passes and approximately midway between said bafiie 8 and the top of said bridge wall to a point substantially beyond said bridge wall and approximately level with the top thereof; and a passage Z between said bafiiessaid passage being substantially devoid of tubes for generating steam whereby a smokeless character of flame is approximated in said passage. y r I 7. In a water tube boiler, in combination, a bank of inclined water tubes, transverse baffles dividing said bank into a plurality of passes beginning at-the steam uptake end, a furnace and a bridge wall therefor, a combustion chamber at the rear of said bridge wall, a baffle 6 forming a roof for said furnace and extending beyond the bridge wall, tubes for supporting said baflie, a baffle 8 extending forwardly from the rear to the first pass and supported on the lower row of tubes of said bank and forming with said from the first pass under and adjacent to the second pass, a lower baffle 6 extending beneath the first and second passes, said baffles forming a passage extending from the furnace forward beneath the second pass and discharging into the first pass, a row of water-tubes buried in said battle 6, a manifold at the end of said baflie 6 for said row of tubes, a protecting wall 15 for said manifold and a water-tube 16 supporting said protecting wall.

9. In a water-tube boiler,-in combination,

the bank of inclined water-tubes, means 1 whereby the same is divided into a plurality of transverse passes beginning at the steam up-take end, a passage extending backthe second pass and discharging into the first pass, and a depending wall in said passage whereby the flanie is deflected clownward and thereby shortened.

10. In a water-tube boiler, in combination, the bank of inclined water-tubes, means whereby the same is divided into a plurality of transverse passes beginning at the steam up-take end, a passage extending backward from the furnace and forward beneath the second pass and discharging into the first pass, a depending wall in said passage whereby the flame is deflected downward and thereby shortened, and a water-tube whereby said depending wall is supported.

In testimony whereof, we have hereunto signed our names in the presence of two subscribing witnesses.

MIN OTT W. SEWALL. DAVID S. JACOBUS.

lVitnesses; B

EDITH CAMP, ROBERT S. DALENZ.

avard from the furnace and forward beneath 

